Simpson, 32, gave birth to her first child, a daughter named Maxwell, May 1. She is engaged to former NFL tight end Eric Johnson, also 32.
"Motherhood is a dream," Simpson told Couric in her first TV interview since having the baby. "It really is absolutely amazing. She had her first flight yesterday, she came to New York with me. .... And did not sleep. She did not sleep. She slept the last hour but she didn't cry. She just wanted to babble. She's doing the babble thing and she just started laughing ... which is the best noise I've ever heard in my life."
Asked if she and Johnson have set a wedding date yet, Simpson replied: "We have not. We haven't had time. Maxwell has definitely taken up all of our time. And I want to do a really big, fun wedding with all of my friends and family."